This invention relates to a dry etching apparatus of a multi-chamber type for successively etching an object, such as a metal, a semiconductor, an insulator piece.
In general, a dry etching apparatus is superior to a wet etching apparatus in view of delineation of fine etching patterns, facility of operation, and disposal of waste solutions, and is therefore prone to be widely used in semiconductor device fabrication.
A dry etching apparatus of a planar type comprises a plurality of etching chambers arranged along a circle having a predetermined diameter or along a straight line. In addition to the etching chambers, at least one chamber is arranged for entrance and exit of each object. A pair of electrode members are disposed in each etching chamber. Each object is successively etched in the etching chambers with each object placed on one of a pair of electrode members. With the dry etching apparatus of the multi-chamber type, it is possible to consecutively etch a succession of objects with a high productivity. Therefore, such an etching apparatus tends to be widespread for semiconductor device fabrication.
However, it is difficult to obtain excellent uniformity in etching characteristics. This is because an etching rate has a nonuniform distribution in each etching chamber. The nonuniform distribution does not substantially vary from one etching chamber to another. In addition, electric power is wasted by the electrode members because each etching chamber has a useless space which is not contributive to etching operation. Therefore, the etching rate is comparatively low for the electric power consumed by the etching apparatus.